Due to fungicide restrictions, harsh winters and special light/temperature combinations at high latitudes, turfgrass variety testing in USA, UK or central Europe has limited relevance for Scandinavia. Thus, trials comparing 41 varieties of seven turfgrass species/subspecies on USGA-greens at two sites in each of the two major climatic zones in Scandinavia were evaluated from 2007 to 2010. Once established, the trials were mowed at 3 mm for bentgrasses and 5 mm for chewings fescue (FRC), slender creeping red fescue (FRL), perennial ryegrass (LP) and rough bluegrass (PT). Mean fertilizers rates in the evaluation years were 1.7 kg N/100 m2 to creeping bentgrass (AS) and PT and 1.0 kg N/100 m2 to the other species. As the trial at Östra Ljungby had to be closed in 2009, species and varieties were ranked based on overall performance (visual merit) at Landvik in zone 1 and Apelsvoll and Korpa in zone 2.
On average for varieties within species, red fescue, especially chewings fescue (FRC), had significantly less winter damage (both biotic and abiotic damage) than perennial ryegrass and the bentgrasses in both climatic zones. The red fescues also had significantly less in-season diseases (mainly Microdochium and Pythium) compared with colonial (ACAP) and velvet bentgrass (ACAN) in zone 1 and in comparison with all bentgrasses in zone 2. On average for all sites, ACAN had higher tiller density, better dormancy color and less height growth, but it also accumulated more thatch than any other species. On average for varieties, the ranking of species was ACAN>AS>FRC>FRT> ACAP>LP>PT in climatic zone 1 and FRC>FRT>ACAN>AS>ACAP> PT>LP in climatic zone 2.
Variety differences within each species at each of the three test sites were mostly significant, but interactions also suggested that different varieties should be preferred in the two climatic zones.
Read more in the Final report - see below!